The Go programming language supports recursion (the process of repeating items in a self-similar way). That is, it allows a function to call itself. But while using recursion, programmers need to be careful to define an exit condition from the function, otherwise it will go on to become an infinite loop.
func recursion() {
recursion() /* function calls itself */
}
func main() {
recursion()
}
Recursive functions are very useful to solve many mathematical problems such as calculating factorial of a number, generating a Fibonacci series, etc.
The following example calculates the factorial of a given number using a recursive function:
package main
import "fmt"
func factorial(i int)int {
if(i <= 1) {
return 1
}
return i * factorial(i - 1)
}
func main() {
var i int = 15
fmt.Printf("Factorial of %d is %d", i, factorial(i))
}
When the above code is compiled and executed, it produces the following result:
Factorial of 15 is 1307674368000
This next example shows how to generate a Fibonacci series of a given number using a recursive function:
package main
import "fmt"
func fibonaci(i int) (ret int) {
if i == 0 {
return 0
}
if i == 1 {
return 1
}
return fibonaci(i-1) + fibonaci(i-2)
}
func main() {
var i int
for i = 0; i < 10; i++ {
fmt.Printf("%d ", fibonaci(i))
}
}
When the above code is compiled and executed, it produces the following result:
0 1 1 2 3 5 8 13 21 34
